[PATCH 1/2] mingw: demonstrate a problem with certain absolute paths

From: Johannes Schindelin via GitGitGadget <gitgitgadget@gmail.com>
Date: Dec 10, 2018, 18:47 UTC
Message-ID: <09a73fe1d30c9fedc2f010fe4df75a9cb000389c.1544467631.git.gitgitgadget@gmail.com>
In-Reply-To: <pull.96.git.gitgitgadget@gmail.com>

From: Johannes Schindelin <johannes.schindelin@gmx.de>

On Windows, there are several categories of absolute paths. One such category starts with a backslash and is implicitly relative to the drive associated with the current working directory. Example:

	c:
	git clone https://github.com/git-for-windows/git \G4W

should clone into C:\G4W.

There is currently a problem with that, in that mingw_mktemp() does not expect the _wmktemp() function to prefix the absolute path with the drive prefix, and as a consequence, the resulting path does not fit into the originally-passed string buffer. The symptom is a "Result too large" error.

Reported by Juan Carlos Arevalo Baeza.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
---
 t/t5580-clone-push-unc.sh | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/t/t5580-clone-push-unc.sh b/t/t5580-clone-push-unc.sh
index ba548df4a9..c2b0082296 100755
--- a/t/t5580-clone-push-unc.sh
+++ b/t/t5580-clone-push-unc.sh
@@ -17,14 +17,11 @@ fi
 UNCPATH="$(winpwd)"
 case "$UNCPATH" in
 [A-Z]:*)
+	WITHOUTDRIVE="${UNCPATH#?:}"
 	# Use administrative share e.g. \\localhost\C$\git-sdk-64\usr\src\git
 	# (we use forward slashes here because MSYS2 and Git accept them, and
 	# they are easier on the eyes)
-	UNCPATH="//localhost/${UNCPATH%%:*}\$/${UNCPATH#?:}"
-	test -d "$UNCPATH" || {
-		skip_all='could not access administrative share; skipping'
-		test_done
-	}
+	UNCPATH="//localhost/${UNCPATH%%:*}\$$WITHOUTDRIVE"
 	;;
 *)
 	skip_all='skipping UNC path tests, cannot determine current path as UNC'
@@ -32,6 +29,18 @@ case "$UNCPATH" in
 	;;
 esac
 
+test_expect_failure 'clone into absolute path lacking a drive prefix' '
+	USINGBACKSLASHES="$(echo "$WITHOUTDRIVE"/without-drive-prefix |
+		tr / \\\\)" &&
+	git clone . "$USINGBACKSLASHES" &&
+	test -f without-drive-prefix/.git/HEAD
+'
+
+test -d "$UNCPATH" || {
+	skip_all='could not access administrative share; skipping'
+	test_done
+}
+
 test_expect_success setup '
 	test_commit initial
 '

-- 
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